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Tank ClosuresTank Closures

A General Guide to a Closure ReportA General Guide to a Closure Report

Missouri Department of Natural Resources

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MRBCA Forms and Notifications

• Submittal of forms CN-1 and CN-2 30 days prior to UST Closure

• Provide notification to DNR Tanks 3 days prior to the beginning of closure activities (Phone 573-751-6822)

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MRBCA Forms and Notifications Con’t

• Call the spill hotline (573-634-2436) once contamination is confirmed (staining, odor, etc.)

• Forms CR-1, CR-2, and CR-3 as part of the closure report. CR-1 includes the signature of the UST owner/operator.

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Closure Report

Submittal within 45 days of the completion of closure activities

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Closure Report Inclusions• Narrative• Site Map• Color Photographs• Laboratory Data• Disposal/Cleaning Documentation• Tanks and Tank Cleaning• Soil and Water Disposal• Other possible inclusions

(In addition to CR- Forms)

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Narrative• Timeline of site activities• Clearly state site cleanup target levels• Reusable product recovered?• Number of tanks removed and their

observed condition• Number of tanks left in place• Planned future use of site

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Narrative Con’t• Are new tanks to be installed onsite?• Amount of backfill and native soil removed

and its fate• Concrete pad in pit? Its condition?• Groundwater in pit? Removed? Recharge

within 12 hours?• Bedrock present?

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Site Maps• Drawn to scale• Current onsite buildings• All adjacent property use• Location of tanks, excavation boundaries, product

lines, dispenser islands• Depth of excavation• Underground utilities• Downgradient direction and degree of slope• North arrow• Locations of all obtained soil samples

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Color Photos

• Pictures before excavation• Ends and sides of all tanks• Cleaned interior of tanks• Tank pit floor and sidewalls• Product line and dispenser trenches• Tank pad if present

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Color Photos Con’t

• Bedrock if exposed• Sealed USTs/lines that are closed in place• Pictures after completion of closure• Description of photos

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Laboratory Data• Sample results from appropriately obtained

samples (Section 4.4.2)• Sample results for the appropriate COC’s

(Table 5-1)• If TPH-DRO or -ORO detected, 25% (or

min. of two, whichever is greater) of samples w/ highest concentrations must be analyzed for PAHs (Tech. Bulletin 2160).

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Laboratory Data Con’t

• Sufficient sample results from all soil returned to the pit to establish that it was below clean up target levels for the site

• Sufficient sample results for disposed soil• Background sample results for waste oil

sites and pre-1980 gasoline tanks• QA/QC documentation

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Laboratory Data Con’t• A complete chain of custody with all

signatures, as well as the dates and times the samples were obtained and subsequently relinquished to the laboratory, and the temperature of the samples as they were received by the laboratory

• Laboratory reporting limits must meet the Required Reporting Limits as outlined in Table 5-3 of the MRBCA guidance document

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Tanks and Tank Cleaning

• Photographic documentation and a signed statement by the party performing tank cleaning activities attesting to the proper cleaning of the tanks

• A signed statement by the UST owner or the owner/operator of the receiving facility attesting to the fate of the USTs

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Tanks and Tank Cleaning Con’t

• Documentation on the fate of any usable product recovered from the USTs

• Proper characterization of the sludge/rinsategenerated during tank cleaning activities as well as the appropriate manifest(s) signed by the generator, transporter, and receiving facility of the waste

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Soil and Water Disposal• Documentation of the proper disposal of

contaminated soil (e.g. landfill disposal receipts, weight tickets)

• Documentation of the proper disposal of contaminated pit water, including: Signed statement of permission from the POTW prior to disposal, documentation of wastewater characterization required by the POTW, and appropriate documentation that the wastewater was accepted by the POTW

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Other Possible Inclusions• If bedrock is encountered in the excavation,

a geologic assessment performed by a registered geologist or a qualified professional engineer is necessary (Section 4.4.2.4)

• If the soil type at the site is declared to be Soil Type 2 or 3, a Soil Type Determination must be made by a registered geologist or qualified professional engineer (March 18, 2005 Soil Type Determination Guidelines)

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Other Possible Inclusions Con’t• If the cleanup target levels are above the

Default Target Levels, the domestic use of groundwater pathway must be evaluated in strict accordance with Sect. 6-3 and Fig 6-2

• If the cleanup target levels are for non-residential use, documentation on the reasonably anticipated future use of the site must be submitted

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Pre-Closure Characterization

• In some cases, RP might benefit from conducting investigations and evaluating gw pathway and RAFU prior to beginning closure activities– Determines whether release has occurred– Allows determination of cleanup standards and

estimation of area exceeding standards prior to digging– Can allow for all necessary actions - closure and

remediation - during one mobilization– At the discretion of the RP– Potentially saves time and money

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Closure Contact Information• Closure Main Phone Line

– (573) 751-6822• Heather Maschler

– Heather.Maschler@dnr.mo.gov• Brett Bottomley

– Brett.Bottomley@dnr.mo.gov• Rick Brown

– Richard.Brown@dnr.mo.gov

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References and Forms

• MRBCA Guidance Document• MRBCA Closure Forms (CN- and CR-)• Technical Bulletin 2160 (PAH analysis)• Soil Type Determination Guidelines• The above may be found at:

http://www.dnr.mo.gov/env/hwp/tanks/mrbca-pet/mrbca-pet-tanks.htm

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QUESTIONS on the DNR QUESTIONS on the DNR Closure Report Presentation?Closure Report Presentation?

Missouri Department of Natural Resources

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UST Closures Using Missouri Risk Based

Corrective Action (MRBCA)

Daniel L. Henry Petroleum Storage Tank Insurance FundDaniel L. Henry Petroleum Storage Tank Insurance FundMay 2007May 2007

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UST Closure Typical UST Closure SequenceTypical UST Closure Sequence

Removal of tanks and backfill Removal of tanks and backfill Site characterizationSite characterizationRemediationRemediationIssuance of an NFAIssuance of an NFA

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UST Closure cont.

Resulting potentially in aResulting potentially in aLonger life of projectLonger life of projectAdditional costs Additional costs

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UST Closure cont.

PSTIF Preferred SequencePSTIF Preferred SequenceDevelop of an Exposure Model (EM) for Develop of an Exposure Model (EM) for the site prior to closurethe site prior to closureDetermine cleanup standards for the tank Determine cleanup standards for the tank pit and piping runs based on the land use pit and piping runs based on the land use and groundwater use assessmentand groundwater use assessmentUse appropriate Tier I Soil Type 1 Use appropriate Tier I Soil Type 1 standards: residential (Table 7standards: residential (Table 7--1a), non1a), non--residential (Table 7residential (Table 7--1b)1b)Removal of the tank systemRemoval of the tank system

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UST Closure cont.

Resulting potentially in a Resulting potentially in a A shorter life of project A shorter life of project –– Quicker Quicker NFANFAOverall cost savings Overall cost savings

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Pre-Closure Risk Assessment

Tier 1 Risk AssessmentTier 1 Risk Assessment

Tier 2 Risk assessmentTier 2 Risk assessment

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Over Excavation Outside the Tank Pit During Closure

For the Fund to pay for substantial overFor the Fund to pay for substantial over--excavation out side of the tank pit and excavation out side of the tank pit and piping runs, typically a Tier 2 risk piping runs, typically a Tier 2 risk assessment will be necessaryassessment will be necessary

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Risk Assessment Prior to Closure

In some situations a preliminary Tier 2 risk In some situations a preliminary Tier 2 risk assessment, prior to closure, may be assessment, prior to closure, may be appropriate while in others a complete Tier appropriate while in others a complete Tier 2 risk assessment may be appropriate 2 risk assessment may be appropriate

Site has already had a release and is Site has already had a release and is completely or partly characterizedcompletely or partly characterizedProperty sale or redevelopment require Property sale or redevelopment require expedited completion of cleanup once expedited completion of cleanup once startedstarted

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RA Prior to Closure, cont.

For sites with an established claim, we can For sites with an established claim, we can prepre--approve costs of Tier 1/Tier 2 as part of approve costs of Tier 1/Tier 2 as part of existing claim existing claim For sites with no previous releaseFor sites with no previous release

Need confirmation of contamination Need confirmation of contamination before costs can be recognizedbefore costs can be recognizedSample(s) for landfill preSample(s) for landfill pre--qualification qualification permit can be used to satisfy this permit can be used to satisfy this requirement. requirement.

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RA Prior to Closure, cont.

Once impacts are documented, we can Once impacts are documented, we can recognize costs for site characterization and recognize costs for site characterization and risk assessment prior to UST closurerisk assessment prior to UST closureProvides more options and more latitude for Provides more options and more latitude for tank owners and operators in accomplishing tank owners and operators in accomplishing cleanupcleanup

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Conclusions

Use of DTLs for UST closure is often Use of DTLs for UST closure is often conservative and unnecessarily expensiveconservative and unnecessarily expensiveUsing an exposure model allows the use Using an exposure model allows the use of appropriate Tier 1 Soil Type 1 look up of appropriate Tier 1 Soil Type 1 look up table (residential or nontable (residential or non--residential) to residential) to determine appropriate disposition of tank determine appropriate disposition of tank pit backfillpit backfill

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Conclusions cont.

Also gives you the option of doing a Tier 2 Also gives you the option of doing a Tier 2 assessment prior to UST closureassessment prior to UST closureThis gives you maximum flexibility to meet This gives you maximum flexibility to meet your clientyour client’’s needss needs

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QUESTIONS?